The present invention relates to the auditory testing of individuals for an assessment of vigilance or for an attention deficit disorder.
It is common practice that a continuous performance test (CPT) form part of the physical examination for attention deficit disorders. The continuous performance attention test has been in use since the mid 50's (Rosvold et al., J. of Consulting and Clinical Psychology 20: 343-350, 1956), with computerized versions available in the 1970's (Greenberg, Psychopharmacol. Bull. 23: 279-282, 1987).
A diagnostic assessment of psychological conditions can be made by conducting a sequence of continuous performance tests where information is recorded to reflect the number of target stimuli correctly identified, the number of target stimuli missed, the number of responses to non-target stimuli, the number of non-target stimuli correctly missed, and the final interstimulus interval (U.S. Pat. No. 5,940,801). Improvements have been made to this method for evaluating attention deficit hyperactivity disorder (ADHD) in children by the incorporating an analysis of the test subject's movement patterns into the evaluation (see Teicher et al., J. Am. Acad. Child Adolesc. Psychiatry 35: 334-342, 1996). A version of such a testing system (the OPTAx™ test system) is now commercially available.
Auditory tests have also been employed for assessing an individual's vigilance. The Test of Variables of Attention (TOVA) and Integrated Visual and Auditory (IVA), tests are computerized go/no-go paradigms in which stimuli are presented in a series and subjects respond to target stimuli. In the TOVA test (see Forbes, J. Clin. Psychol. 54:461-476, 1998), the subject is instructed to respond to one tone as soon as it is heard by pressing a key and not to respond to the other tone. The IVA test (see Tinius, Arch. Clin. Neuropsychol. 18:439-454, 2003) uses both visual and auditory stimuli.
In another example, (see Gopher and Kahneman, Perceptual and Motor Skills 33:1335-1342, 1971) the auditory test involves the simultaneous presentation of different stimuli to each ear. Upon hearing an auditory cue in one ear, the subject is asked to report any subsequent number words presented to that ear, ignoring non-number words and any stimuli presented to the other ear. This test has been applied to pilots and air traffic controllers (see Boer et al., Mil. Psychol. 9:137-149, 1997).
Dichotic listening tests have also been used to assess hemispheric differences in language processing. In one example (Springer et al., J. Nerv. Ment. Dis. 179:459-467, 1991), the test consisted of precisely timed paired words presented to the right and left ears. The words were of equal duration and sound. After each presentation, subjects were asked by the examiner to identify the words or word that they heard by pointing to cards listing the stimuli used. It was found that brain-injured patients with dysphoric mood and symptoms suggestive of temporal lobe epilepsy would often recognize only one of the presented words. As in the previously described auditory test, the subject was cued to the occurrence of the stimulus.